Power converters, such as DC-DC power converters that convert an input voltage to a typically lower output voltage are known in the art. In DC-DC power converters, the output voltage is typically controlled using a feedback loop (feedback circuit) in dependence on an actual value of the output voltage and/or an actual value of a coil current flowing through a coil of an output filter of the DC-DC power converter.
In such DC-DC power converters however, when a fast transient occurs at the output side of the DC-DC power converter, e.g. due to a sudden switch or change of the load (such as removal of the load, for example), the feedback loop might open, i.e. an open loop condition of the feedback control by the feedback loop might occur. This condition is due to the fact that the coil current is not capable of following the sudden change of the load since its current slew rate is limited by the inductivity of the coil via the well-known relationship dl/dt=V/L.
The open loop condition of the feedback loop may result in ringing (i.e. an unwanted oscillation of the output voltage and/or the load current) due to the step response of the output filter, which is not damped anymore by control of the feedback loop. Such ringing may cause damage to the components of the DC-DC power converter and should be avoided.